No. He just carried the torch farther than Willis O'Brien. Sadly, with the exception of King Kong and 1929s The Lost World most of O'Brien's other work was either abandoned or lost. Harryhausen learned from O'Brien and his first major work came on Mighty Joe Young as assistant animator. If I remember right he said he did the lions in the fight with Joe at the ranch and further assisted in the nightclub scenes.

From there he carried the torch into so many movies blazoned in childhood memory. How many people he inspired to create what we see today in all forms of movie creation, we'll never know. But, Willis O'Brien started it all. Thankfully they both were masters of their craft.

Stop motion is hard, laborious, tedious work that takes great concentration. It's usually not appreciated like it should be... but maybe that's just me.